Strontium has 38 protons (necessarily!), and 38 electrons (necessarily), and has generally 48, 49, or 50 neutrons depending on the isotope.What is the mass number of strontium?
Answer and Explanation: The molar mass of strontium is 87.62 g/mol. This means one mole of strontium has a mass of 87.62 grams.What has 53 protons and 74 neutrons?
The most common, stable form of iodine has an atomic number of 53 (protons) and an atomic weight of 127 (53 protons plus 74 neutrons). Because its nucleus has the "correct" number of neutrons, it is stable and is not radioactive.